Have you heard the one about Bush's single-digit IQ? Everyone working on the Bush campaign sure hopes you have  and that you remember it as you sit down to watch Tuesday night's showdown between the Texas governor and Vice President Al Gore.

It's all part of the expectations game  a game the Bush camp is playing very carefully.

Far from hyping their candidate, the governor's staff has adopted an ingratiatory stance as they prepare for the first presidential debate. "Vice President Gore has a carefully schooled and trained technique," Bush communications director Karen Hughes told reporters last month. In other words: We just hope Bush can escape this debate with his dignity intact.

Sound like an undersell? That's exactly what it is; and it's part of a tactic the Bush camp has perfected over the years. After a 1994 debate against then-Texas governor Ann Richards, the press handed underdog Bush a win  because he was composed and his responses were intelligible  even though later review showed Richards to be the victor.

That's the key: Bush is no dummy. He just wants everybody to think he is.

And while Gore knows perfectly well he's not facing an idiot Tuesday night, he's still got to fight the widely held perception that the debate is a sublime mismatch: He's expected to whip this guy, but good. Anything less than a full-scale disembowelment will play as a win for Bush.

Of course, even if those wondrously low expectations do materialize, the 90-minute exchange won't be a cakewalk for the governor: The traditional debate format, with set times for response and rebuttal, appears to favor Gore's stranglehold on the minutiae of public policy. (Subsequent encounters will be more informal.) In order for Bush to hold his own, he needs to keep a few things in check. Like the infamous "smirk," which came under fire after surfacing during several primary debates. And while his charm and quick wit are certainly critical to his success, Bush needs to curb his inclination to use humor at inappropriate moments  as he did during one primary debate, chuckling in response to a question regarding defense lawyers falling asleep during death penalty trials in Texas. If Gore's fault is an obsessive grip on dry policy points, Bush's weakness is just the opposite: A tendency to gloss over issues in favor of a quick joke or gibe.

That sort of avoidance would play very poorly in the press, and maybe even among voters. But a negative reaction is easy enough to avoid: If Bush can maintain a solid grip on the issues at hand, fill his time allotment, avoid any serious verbal gaffes and refrain from cockiness, he has a good shot at walking away from Boston with something resembling a win. To borrow a phrase from his dad's playbook, the governor just needs to "stay the course," keep his head down  and let his sometimes aggressive opponent make the mistakes.

AL GORE

In the last twelve and a half years, Al Gore has debated 35 times as vice president and presidential contender. He's debated in groups, debated one-on-one, debated in town halls and on talk shows. He's debated dwarves like Gephardt and Dukakis, jocks like Jack Kemp and Bill Bradley, wild men like Ross Perot, pushovers like James Stockdale and supposed pushovers like Dan Quayle. He's gotten very good at it, primarily because he has a strategist's nose for weakness and the discipline to keep jabbing at it. And he will hit below the belt.

Gore's first big showdown was his last flop. In Gore and Bill Clinton's 1992 campaign against George Bush, an underestimated Dan Quayle (with James Stockdale there as comic relief) embarrassed Gore with tactics that Gore would later use to great effect: staying on the offensive, hitting where your opponent can't defend himself, keeping him off his guard. Quayle kept Gore silent by aiming right over Gore's shoulder at Bill Clinton with mostly personal zingers to which Gore wouldn't respond. The debate didn't save Bush, or Quayle for that matter, but it seemed that debating  such a public-performance event  was not to Gore's strong suit.

Then came the NAFTA faceoff with Ross Perot. Gore lobbied heavily for the chance to take on the jug-eared billionaire in a forum Perot was at home in, CNN's "Larry King Live," at the height of his popularity/credibility as a national gadfly. Perot had been doing his "great sucking sound" charts-and-graphs act on infomercials and on King's show, and he was aching for a shot at somebody in the pro-NAFTA Clinton Administration, and delighted to get somebody as high up  and as charisma-deprived  as Gore.

But Gore didn't give Perot the economics debate he wanted, instead targeting Perot's obvious weak spot: his temperament. With King obliging as ever, Gore dredged up the disastrous (and catchily named) Smoot-Hawley tariff of 1930, a facile comparison of eras that worked perfectly. Gore handed Perot a framed picture of the pair; he interrupted Perot incessantly, made him lose his temper. Gore's decisive victory was the saving of NAFTA and the beginning of the end of Perot as even a semi-serious public figure.

In 1996 against Kemp, the mismatched running mate of Bob Dole, Gore faced a polished opponent, armed with charm, looks, football stories and a Reaganesque ease that threatened to make Gore look unlikable. So Gore started with a gambit his daughter Karenna thought of: "I'd like to start by offering you a deal, Jack. If you won't use any football stories, I won't tell any of my warm and humorous stories about chlorofluorocarbon abatement." In one stroke, Gore got in a semi-funny self-deprecating wonk joke and got Kemp off his game. Gore spends the rest of the debate picking at differences between Kemp and Dole (watch for this one from George W. Tuesday); unprepared Kemp wilts.

Most recent victim: Bradley. Gore, rusty from four years of uninterrupted vice presidency, once again turned to strategy in his series of matchups with Bradley. He decided to hit the idealism-addicted Bradley where it would surely hurt: right in his lofty ideals. Gore found an opportunity in Bradley's cherished health-care plan, in a $150 voucher proposal that Gore charged would be cruelly insufficient. Bradley fumes and instead of hitting back, becomes caught in clumsily defending his plan. Bradley is beaten as a candidate.

Now Gore is the biggest fight of his life, and dutifully fighting the expectations game in public while he privately prepares for three rounds with George W. Bush that are likely to decide the presidential election. Bush does not have Gore's grasp of the issues, but he has Kemp's charm and some big ideas, and he's also shown an aptitude  see Ann Richards  for the kind of laser-focused performance that can win on television. Gore undoubtedly has a line of attack all picked out, and it will attempt, as usual, to bring out his opponents' unattractive side without looking unattractive doing it.

Gore will hit Bush wherever it hurts. It will up to Bush whether or not he doubles over for the cameras.